The best fix i have found is to buy some special disk cleaner:
Or, if you don't want to spend money, run it under cold normal tap water (the back side of the disk), and then dry it with a 100% cotton rag.
Software will not fix an unreadable disc because it is scratched. PS2 game Discs are not rewriteable and can not be changed so there would be nothing for the software to fix on the disc unless it was a bootleg copy
You replace it with a new game or you purchase another used game disc
try it
With care not to scratch the disc, if the disc is already scratched the cleaning will not help
One of the best ways to fix a scratched disc is to buy a repair kit.
You don't fix a game disc that is scratched you replace it
PS2 are on DVD discs if that is what you mean. Badly scratched Game disc can make the PS2 not know the format, but it is just a bad disc
Often the game disc is scratched and damaged
You must be using the actual PS2 version. If you use a Wii or Xbox version, it will definitely not work. The PS2 is a very old console, and it is likely that your disc is scratched. You can follow <a href="http://www.wikihow.com/Fix-a-Scratched-CD">these</a> instructions on cleaning your disc if it needs it. I hope that helped.
The game disc could be scratched Amazon has a new disc for only $8.68
if it isn't scratched, why would it require fixing? it could be your console that isn't functioning correctly.
Bring it to your local game store and ask if they fix scratched disks.